The present invention generally relates to an automatic merchandise bagging apparatus and, more particularly, to a merchandise delivery conveyor for the automatic merchandise bagging apparatus.
The U.S. Pat. No. 2,958,990, patented Nov. 8, 1960, discloses an automatic merchandise bagging apparatus which comprises a stationary tray for receiving articles to be bagged, a bag receptacle for receiving a bag fed from a bag container accommodating a stack of bags, a bag mouth opening mechanism for opening the mouth of the bag resting on the bag receptacle, a hydraulically operated merchandise loader adapted to be driven by a hydraulic cylinder between stand-by and loading positions in a direction towards and away from the mouth-opened bag on the bag receptacle along the top surface of the stationary tray, and a delivery conveyor unit positioned on one side of the bag receptacle remote from the tray. The bag receptacle with the mouth-opened bag thereon is, after the articles have been loaded or filled into such bag incident to the movement of the merchandise loader from the stand-by position to the loading position, pivoted from a horizontal position towards an upright position to erect the loaded bag with the bag mouth opening upwards.
The delivery conveyor unit employed in the automatic merchandise bagging apparatus of the U.S. Pat. No. 2,958,990 is comprised of a substantially endless belt having one end so positioned adjacent the upright position of the bag receptacle and also adjacent the point of pivot of the bag receptacle that, soon after the bag receptacle has arrived at the upright position, the loaded bag then erected with the bag receptacle held in the upright position is delivered onto the conveyor belt. The delivery of the loaded bag from the bag receptacle onto the conveyor belt is carried out by causing a portion of the bottom of the loaded bag to rest on the trailing end of the conveyor belt with respect to the direction of transportation of the loaded bag to a delivery zone as the bag receptacle being pivoted approaches the upright position and then causing the conveyor belt to run. The conveyor belt is shown as having an effective length sufficient to support a plurality of, for example, three, loaded bags thereon.
The U.S. Pat. No. 3,774,370, patented Nov. 27, 1973, discloses a similar automatic merchandise bagging apparatus utilizing a conveyor belt for the merchandise delivery conveyor. While the bag receptacle employed in the appratus of the second-mentioned U.S. patent is, unlike that disclosed in the first mentioned U.S. patent, supported for pivotal movement between horizontal and upright positions, the point of pivot of the bag receptacle being positioned above the trailing end of the conveyor belt, the delivery of the loaded bag from the bag receptacle onto the conveyor belt is carried out in a manner similar to that effected in the appratus of the first-mentioned U.S. patent.
In both of the automatic merchandise bagging apparatuses, although the use of the conveyor belt is advantageous in that it can support a plurality of successively loaded bags temporarily before one or more of them are taken out from the delivery zone by the same customer or different customers, it has been found that one or some of the loaded bags successively delivered onto the conveyor belt one at a time from the bag receptacle and then being transported by means of the conveyor belt towards the delivery zone tend to fall down on the conveyor belt. This is particularly true where the loaded bags are top-heavy and/or where external shocks or impacts are applied to the loaded bags being transported on the conveyor belt in upright position. Once the bag has been fallen down, some of the articles loaded therein are scattered, thereby rendering not only the customer to be placed in embarrassed position but also the employment of the automatic bagging apparatus to be meaningless.
The copending U.S. patent application Ser. No. 91,816, filed Nov. 6, 1979 and now U.S. Pat. No. 4,306,399, the invention of which has been assigned to the same assignees of the present invention, discloses a unique merchandise delivery conveyor effective to substantially eliminate the above described disadvantages and inconveniences inherent in the prior art automatic merchandise bagging apparatuses. The merchandise delivery conveyor employed in the apparatus of the copending U.S. patent application comprises a generally L-shaped carriage movable between receiving and lifting positions along a guide rail and a bag lift movable between lifting and delivery positions in a direction generally perpendicular to the direction of movement of the L-shaped carriage. The merchandise delivery conveyor is so designed that, after the loaded bag has been transferred from the bag receptacle onto the L-shaped carriage, the L-shaped carriage with the loaded bag thereon is horizontally moved from the receiving position towards the lifting position at which the loaded bag is transferred onto the lifting carriage, the lifting carriage with the loaded bag thereon being then upwardly moved towards the delivery position where the loaded bag is exposed to the outside of the apparatus in readiness for the delivery thereof to the customer.
However, it has subsequently been found that the use of the carriages is less efficient than the use of the conveyor belt because, while the bagging rate of the apparatus of the copending U.S. patent application is high, the delivery unit including the carriages has no space for temporary storage of a plurality of loaded bags. Specifically, unless the customer removes the loaded bag from the lifting carriage as soon as the latter carrying such loaded bag arrives at the delivery position, the L-shaped carriage carrying another loaded bag is held standstill at the receiving position and, on the other hand, the bagging apparatus is held standstill until the L-shaped carrage moves from the receiving position towards the lifting position subsequent to the removal of the loaded bag from the lifting carriage. Where one customer has purchased the articles which require, for example, four bags for them to be filled therein, the customer will be bound to the delivery unit for a relatively long period of time until all of the loaded bags are successively transported one by one to the delivery zone.